Occasional musings on a variety of things.

DC: The Improbability of Earth

A month ago (yes, a whole month), I reviewed chapter three of Ian Wishart’s The Divinity Code. Towards the end, I said:

Ian declares at the end of the chapter that this is going to be a major theme of his book. There are so many things that “could have” been different, therefore we are so lucky to be here that it is unbelievable that our being here is not the result of sentient intention.

Chapter four, “The Improbability of Earth”, continues this theme, so it’s worth recapping the three thoughts with which I ended the last review:

1. The assumption that it is intelligible to speak of what “could have happened” in the universe.

2. The assumption that earth life, or even sentient life at all, is special enough to require special explanation.

3. The assumption that there aren’t “other universes” which fall victim to exactly the sentient-life-less fate we’re told we narrowly avoided, and that this just happens to be one in which sentient life is possible.

Now, both (1) and (3) are more applicable to the preceding chapter than to this one, because while the preceding chapter was about the way the universe happens to be, this chapter is about where in that universe earth happens to be located. The arguments of the chapter can be summed up as follows:

1. Current hypotheses regarding the origin of life on earth are inadequate.

2. A life-producing earth-like planet is so unlikely as to be practically impossible.

3. Scientists believe in God, therefore you should.

There are several assumptions underpinning the arguments in Chapter Four.

The assumption that earth life is the only kind of possible life.

My working definition of “life” is “any self-replicating pattern that has the potential to evolve”. In other words, “any self-replicating pattern that can vary from one generation to the next and exists in an environment of scarcity/competition”. That category includes earth life, but also includes any such self-replicating patterns of which we have not yet conceived or we have not yet discovered.

Wishart spends a lot of time explaining how earth is inexplicably tailored for the arising of life. To be clearer, he is talking about how earth is inexplicably tailored for the arising of earth life. Put in those terms, it doesn’t seem quite so incredible. The reasoning goes like this:

1. Incredibly unlikely things require special explanation.2. (Unspoken assumption: earth life is the only possible kind of life.)3. Earth life required exactly earth’s conditions in order to arise.4. Earth conditions are astronomically unlikely to occur exactly like this.5. Therefore life requires special explanation.

Without the unspoken assumption, the odds of life arising increase by an order of the number of every possible – existent or non-existent – planets with conditions that could give rise to any kind of life (not just earth-like life).

If this is still not clear, consider this analogy:

1. Incredibly unlikely things require special explanation.2. (Unspoken assumption: Ryan Sproull-like people are the only possible kind of people.)3. Ryan Sproull required exactly Ryan’s Life in order to arise.4. A person’s life conditions are astronomically unlikely to occur exactly like this.5. Therefore the existence of a person (me) requires special explanation.

Because we’re familiar with other kinds of people, the flaw in the argument seems obvious to us. But because we’re not familiar with other potential kinds of life (existent or not), the flaw in Wishart’s argument is not so immediately apparent.

It may well be that life of any kind is still unlikely enough to fit Wishart’s criteria for requiring special explanation. Just because life in general is more likely than earth-like life, that doesn’t mean that it is as inevitable as some scientists erroneously believe that earth-like life is. But really, we don’t know what these increased odds are, because we don’t know all of the possible forms of self-replicating patterns in the universe.

All of Wishart’s arguments are based on earth-like life. Many are based on theories of the spontaneous arising of complex life in the form of the simplest cell possible. It may seem like “the simplest cell possible” would be a simple form of life, but really, even a simple cell is incredibly complex. For this reason, molecular biologists have long since abandoned theories of such cells instantly forming, in favour of cells themselves having evolved from simpler processes. No conclusion has yet been reached (see next section).

Wishart refers to a Dawkins argument that addresses the unlikelihood of earth-like conditions arising.

[Dawkins] disarmingly concedes the point. Yes, he admits, we appear to live on a unique planet. Yes, the moon is crucial for the existence of life [note the implicit equating of “life” with “earth life”]. Yes, we inhabit the Goldilocks zone.

“Earth’s orbit,” he agrees, “is so close to circular that it never strays out of the Goldilocks zone.”

Faced with all of this, Dawkins tries to convince readers that despite everything having to be “just right”, science still has a natural answer.

“The great majority of planets in the universe are not in the Goldilocks zones of their respective stars, and not suitable for life [now Dawkins making the earth-like life assumption]. None of that majority has life. However small the minority of planets with just the right conditions for life may be, we necessarily have to be on one of that minority, because here we are thinking about it.”

Simple, really. Using Dawkins’ logic, you can wave all the unlikely preconditions aside, put it down to blind chance, and say, “Well, here we are, then, so it must have happened naturally.”

Richard Dawkins’ fatal mistake here is the assumption that his very existence and ability to ponder the probability of it all proves in itself a natural first cause.

A subtle misreading of Dawkins’ argument lies behind Wishart’s responses. To hear Wishart tell it, Dawkins’ argument is, “We are here, therefore it happened naturally.” That is not what the quoted argument is saying. Instead, it is saying, “If it happened naturally, here we would be. Here we are, so it could have happened naturally.” And it is in response to the design argument, “Here we are, so it couldn’t have happened naturally.”

The Assumption that Not Knowing Means God Did It

We don’t currently know for sure how life arose on earth. Without a time machine, we will never know for certain. Hypotheses can be forwarded that fit the observable facts, but by their very nature they are untestable. We cannot observe what happened millions of years ago, and we cannot reproduce conditions that include millions of years of time. There is a gap in our knowledge and there will continue to be so.

So unlike many other objects of enquiry in science, there cannot be conslusive proof of a given abiogenesis hypothesis. This also means that conclusive proof is an impossibly high standard to demand from origin-of-life theories. Any argument that rests on the lack of such inconclusive proof is an argument that rests on an unfalsifiable premise, and so is flawed.

What we have with appealing to God when science has no conclusive explanation is the “God of the gaps”. The gaps continue to shrink, as scientific explanation expands, but the gaps are still there, and so the God of the gaps persists. What we have here is a situation where the gap will never completely disappear – it is beyond the ability of science (unless we sort out time travel) to conclusively fill the origin-of-life gap. And so it is a place where the God explanation can sort of surviveo forever if needs be.

Wishart is a big fan of pointing out improbabilities. What are the odds that, with every other phenomenon having a naturalistic explanation, the one that cannot have a conclusively proven naturalistic explanation is the very phenomenon that has only a supernatural explanation? Incalculable, but I’d say they’re pretty slim. They’re certainly slim enough for me to give naturalistic explanations the benefit of the doubt.

The Assumption that Life is Special

This is the really big one, of course. We can give Wishart’s arguments the most possible benefit of the doubt, and yet this assumption remains. We can give his argument the unwarranted assumption that life of any kind is so unlikely as to be practically impossible. We can give his argument the unwarranted assumption “God did it” is an appropriate response to something that demands explanation. But we are still left with the anthropocentric assumption that life demands a special explanation.

To be more clear, the assumption is that life demands a more special explanation than any other phenomenon does. In other words, two hydrogens and an oxygen forms water, splitting uranium atoms releases energy, gravity pulls everything together – all of these could be true and it would just be a boring old universe anyone could imagine floating around. Add life – especially sentient life – and suddenly it becomes a universe that demands an explanation.

There is simply no logical reason for this leap. The formation of a particular kind of crystal may be incredibly unlikely and rare, and occur in this universe, but that does not mean that the universe now requires special explanation, nor does the occurrence of this crystal require special explanation. The same holds true for life. While life may be very important to the living, its importance does not hold outside of its own self-reflection, regardless of the odds of it occurring.

There is no objective standard of importance against which we can judge ourselves to be more important than a quasar, and so there is no means of singling this universe out among the infinite imaginable potential universes against which we compare this one when we say that it is unique, life-bearing and important.

I may write a little more on abiogenesis and potential non-earth-like forms of life later.

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15 Comments →DC: The Improbability of Earth

The venerable Terry Pratchett after talking about anthropic principles and related thinking:

The universe clearly operates for the benefit of humanity. This can be readily seen by the way the sun comes up in the morning, just when people want to start their day

You make a good point about whether life is something so unusual we need to go to a special effort to explain it. There are plenty of physicists that seem to think that once particles started condensing out the big bang then elephants where more are less inevitable. Being a biologist I don’t quite take that view (it would rather limit my ability to find a job for one) but it is true that at it’s most basic level life is just chemistry – there is no need to imagine a vis vitae running through all life and setting it apart from the rest of the world.

Anyway, those are my thoughts. It seems to me, from what I can gather, that the DC is a little ahead of Eve’s Bite for scholarship. I read the evolution chapters of the latter in a bookshop and was appalled and amused in equal parts by the lack of understanding of what was being argued so decided to not press on and see how all those ‘isms’ were going to do-in Western Culture where this one appears to be slightly more grounded in fact?

Just jumping in on one quick little point, Ryan.. your argument about the uniqueness of Ryan Sproull was raised with me (in the context of Cambridge astronomers) a week or so ago, so I assume it is a generic argument doing the rounds.

The point I made there, privately, is worth making here also. The context is set too narrowly. You exist, but so do I and six billion others.

Here’s the challenge to me and my response:

“Very interesting and shows a vast range of reading. However, If I may say, I have serious reservations about your approach.“1. It is NOT scientifically established that the Universe was “created” in the sense you mean.

[It can never be “established” one way or the other. It was a singularity, unrepeated in history. What I am arguing is that the event fits the biblical picture and that leading scientists are acknowledging as much. What I am arguing is that the leading naturalistic arguments are ultimately appealing to a faith-based answer (unprovable by empirical science), meaning readers can make of that what they will. ]

“2. The Fine-Tuning argument is patent wishful thinking It goes like this; – If an all-powerful god made the world so that Cambridge Cosmologists would thrive – Then Cambridge Cosmologists would thrive – Arguably Cambridge Cosmologists do thrive Conclusion: An all-powerful god made the world so that Cambridge Cosmologists would thrive.

“The problem with this argument is that Cambridge Cosmologists can be replaced with anything (including yours truly or tape-worms) and therefore is vacuous.”

[Your context is set too vaguely. If Cambridge Cosmologists, and only Cambridge Cosmologists, appeared to exist, this would be a closer analogy to the situation we currently find ourselves in…It was Dawkins himself who chose to invoke “great numbers” in the probability debate. Under those big numbers however, we find ourselves as the only sentient species on the planet, on the only planet capable of sustaining sentient life in our solar system. We find not only one convenient accident had to take place for our survival, but a whole string of such things where the coin could have flipped one way but went ours instead. (I use coins only as an analogy, not a real example of probability because the 50-50 odds on a coin are far better than the ones laid out in TDC.)

There comes a point where, even in scientific debate, the laws of statistical probability must enter into the debate itself, rather than remain as the elephant in the room.

Sure, all these things could have happened by “chance”. Perhaps we’re the luckiest species in cosmic history because the universe fluked it and threw up possibly the only species capable of appreciating it.

But the odds against this are so astronomical they make the vastness of space and time irrelevant. Not nil, but so near to nil that the best supercomputers on the planet would still write the number as zero.

And even if you cling to that next to nil chance of the random origin of human life, that doesn’t get around the other factor in the equation: the existence of the universe itself without appealing to religious scientism.]

NOW, that was my response to the individual who emailed me. You raise a good point about earth-life, Ryan, but I do in fact cover that off in the book. Chemists are confident that we have a very solid knowledge of the atomic table in regard to all the stable elements that could possibly exist (and thus support self-replicating and evolving patterns of any kind). If you know anything about atomic structure you’ll know their logic is sound – add protons, neutrons and electrons and you are dealing with a different element, so up the table we go.

It is possible that there are some radioactive substances remaining to be discovered, but for fairly obvious reasons (their inherent instability) they are unlikely in the extreme to form a basis for life.

Chemists have further figured that the elements most likely to support self-replicating patterns are going to be either carbon-based, or silicon based.

Experiments with silicon have found it to be a magnitude more unlikely to support life structures than carbon.

If one debates this at a kind of scientific fiction/fantasy level, without recourse to chemistry, physics and the atomic table, one can theorise that there might be all sorts of planets with different conditions favouring different kinds of life.

But the reality is, the stardust we and earth are made from is the same stardust infesting the rest of the universe. The laws of physics and chemistry don’t magically change once you leave earth.

The point of these chapters is that cutting edge, top of their field types like Shapiro, Crick etc are acknowledging the size of the problem. If it was as easy as wishing up a totally new kind of lifeform base, don’t you think they would have published to that effect?

Even Shapiro, in his “rock” theory of metabolistic evolution is not suggesting that rocks are actually alive, merely that rigid structures might provide a stable enough environment for organic material to develop.

Regardless, he admits that such a path if proven (and it hasn’t been) would lead nowhere near DNA.

The best brains in science are working on these issues. If life could arise in other forms, you would expect to see it here on earth. There is such a vast biosphere from bacteria to humans that there is surely room for other types of self-replicating patterns to co-exist. But we don’t see them.

And while I’ll leave the bulk of your comment, ‘investigate’, to Ryan (as is only fair, I think) I’m concerned about one point. The challenge you quote gave the following argument:

– If an all-powerful god made the world so that Cambridge Cosmologists would thrive– Then Cambridge Cosmologists would thrive– Arguably Cambridge Cosmologists do thriveConclusion: An all-powerful god made the world so that Cambridge Cosmologists would thrive.

And called it vacuous. And your comment was that the context of the original argument (that this one criticises) wasn’t considered.

You then seem to be say that you consider such an argument, only with “the only sentient species on the planet, on the only planet capable of sustaining sentient life in our solar system” replacing “Cambridge cosmologists” would be, and is, acceptable. Is that actually your position? (In good faith, I’d hate to misconstrue your position here.)

Because, more vitally than the argument essentially being a vacuous conditional, it also badly begs the question.

Look again:

– If an all-powerful god made the universe such that the only sentient species on the planet, on the only planet capable of sustaining sentient life in our solar system would thrive,– Then [blah blah blah].– Arguably [blah blah blah].Conclusion: Then an all-powerful god made the universe such that the only sentient species on the planet, on the only planet capable of sustaining sentient life in our solar system would thrive.

All the premises except the first do no work, and the argument provides no reason to accept the first premise other than the conclusion. It’s a trusim. It’s A implies A.

So, I think such an argument can’t be used to establish any position, regardless of which particular propositions you’re considering.

Perhaps the criticism given by the person you were responding to was an bad paraphrase of your original argument? I don’t really see how it’s relevant to the Ryan-Sproull-world argument in the original post.

In any case, is there any real purpose in criticising the “Cambridge cosmologists” form of the argument as having its “context […] set too vaguely” when it is supposed to be an ad absurdum, and so is supposed to be unconvincing? Isn’t the point of the critique that the original argument, regarding all the people on Earth, might also have its context set too vaguely, and may be ignoring other possible sentient life?

I think it’s a little misguided to attempt to “prove” God, and ID arguments are inherently metaphysical. Nonetheless ID offers an alternate answer to the big existential questions, whereas secularists glibly deny that there is no WHY, things are just “there” for no reason other than mindless physical processes. This is spiritually and intellectually inadequate.

I think it’s a little misguided to attempt to “prove” God, and ID arguments are inherently metaphysical. Nonetheless ID offers an alternate answer to the big existential questions, whereas secularists glibly deny that there is no WHY, things are just “there” for no reason other than mindless physical processes. This is spiritually and intellectually inadequate.

I think that neither ID nor rational science even address existential questions. The word “why” can mean two different things – “what is the cause?” and “what is the purpose?” ID and rational science are answering the question, “What is the cause?” It is not the place of science (nor of pretend science) to answer questions about the meaning of life. It’s beyond their scope. Life is not made meaningful by the introduction of an enormous powerful creator and life is not made meaningless by naturalistic explanations.

People just misunderstand the limits of science. They mistakenly think that because science is very very good at working out how things happen, it should therefore be applicable to questions like, “How should I live?” and, “What is the purpose of my life?”

There is no such thing as a scientific way of living, but people are under the impression there is.

It’s understandable, I suppose, considering religion has been overstepping its own bounds for thousands of years. Religion’s job is to tell people how to act and why they’re here, not the cause of mental illness or the origin of life. And similarly, science’s job is to tell us how stuff works and how we can make it work for us, not whether or not abortion is right or what kind of values to instill in our children.

Religion’s about good/bad. Science is about true/false in the physical world. Never the twain should meet.

Ryan, I appreciate the point you are trying to make, but when you emphatically state “Life is not made meaningful by the introduction of an enormous powerful creator”, I’m fighting (and failing evidently) the urge to say, “Says who?”

I would have thought that, objectively, if you were created by a divine being, it automatically gave your life purpose regardless of whether the created thing thinks so or not.

A dumb machine made by a human still has a purpose for its existence, regardless of whether it recognises it.

Dominic, the danger of responding to witty absurdities is that the debate can take on a life of its own well and truly out of its original context.

In The Divinity Code, I tackle a similar line of argument from Dawkins, in regard to the possibility of multiple universes – we just happen to live in the one universe where the highly improbable happened.

…Before leaving this section, it is worth examining what another of atheismâ€™s â€œrock starsâ€, Richard Carrier at Infidels.org, has to say about the cosmological scientific evidence for God. Carrier, a historian studying for his Ph.D. and currently working as a librarianâ€™s assistant, is a strident opponent of any claims that God had a hand in anything. Naturally, this fine-tuning issue is like swallowing a sea-urchin intact for Carrier, and he argues strongly that we shouldnâ€™t leap to conclusions.66

â€œWhile the creationist thinks God explains the â€œfine tuningâ€ of the universe, he fails to see that every possible universe which can contain intelligent life will appear â€œfine tunedâ€ no matter what its cause.â€

I donâ€™t know that I accept his reasoning. Look at it another way. The reason science is increasingly getting excited about the â€œfine tuningâ€ is because we appear to be alone. A universe teeming with life on every planet would not raise suspicions about fine tuning; if life arose here, there and everywhere then there would appear to be nothing particularly special about the residents of Planet Earth.

Carrierâ€™s argument is only valid if the â€œevery possible universeâ€ he talks of turns out to have just one planet with life on it. In that case, I agree, the residents of every universe would have reason to feel suspicious and â€˜fine-tunedâ€™. But employing the multiple universe theory is the scientific equivalent of reaching for an old alchemy textbook, or perhaps Hogwartâ€™s Invisible Book of Invisibility. We canâ€™t see any other universes. We canâ€™t reach any other universes because, by definition, the laws that govern this universe prevent that. Nor is there a shred of evidence that any other universe can, or does exist. And even if it does, as cosmologist Paul Davies notes, it only pushes the first cause problem back from â€œwho created the universe?â€ to â€œwho created all these universes?â€

Carrier, funnily enough, doesnâ€™t want to admit that he has a problem here.

â€œWe already have evidence that universes exist (we live in one), and so we already have some grounds for positing multiple universes to explain the parameters of ours, e.g. there may be a million universes with different parameters and only one has life (and thus we are in it, since that is the only place we could be). This is no more ad hoc than positing God, and is arguably less so, since there is less reason to invoke an unknown type of entity (a god) than a known one (a universe).â€

Again, sounds plausible. For a nano-second.

We know â€œuniverses existâ€, he says, because â€œwe live in oneâ€ [my emphasis, really it should be â€œwe know a universe exists because we live in itâ€, because there is not the slightest piece of scientific evidence that universes exist, or are even capable of existing] therefore it is reasonable to assume millions of universes exist.

On that logic, my clone could be God. After all, I exist so there could be billions of me and, using Dawkinsâ€™ dodgy math, one of the other Ian Wisharts is actually quite likely to be God. Or maybe Iâ€™m a â€œuniverseâ€ in one of my other lives. Do I hear faint yelps of â€œFlying Spaghetti Monsterismâ€67 in the darkness? There is a point…

(Footnote 67 A favourite atheist argument is to claim the universe could equally have been created by a â€œflying spaghetti monsterâ€, which is really an appeal to the absurd to make the idea of a divine Creator sound equally daft. Appealing to invisible, undetectable other universes, however, is equally a question of belief, not science. Anyone who appeals to multiverse theory is explicitly admitting the need for a Creator to explain the Big Bang. It is, in essence, an appeal to â€œScience of the Gapsâ€

…when atheists, too, must face the reality that their own religious beliefs transcend scientific evidence and begin to make a mockery of true science. Thatâ€™s fine, if Richard wants to call his god â€œMultiverse Theoryâ€, thatâ€™s his business. But letâ€™s not pretend it is â€œscienceâ€ in any accepted definition of the term….

HERE endeth the extract. In appealing to the possibility of invisible aliens waiting to be discovered, the diehard atheist makes exactly the same appeal to faith that a religious person does. He or she is appealing to Science of the Gaps: the possibility that we “might” discover this in the future.

Given the physics required for interstellar spaceflight (and I cover this in The Divinity Code too), it may actually be impossible for us to reach another star system, let alone send back intelligible data within a useful timeframe.

Which then leaves us with the real question: Why Science of the Gaps instead of God of the Gaps?

If the scientific explanations on origins were remotely convincing, I’d possibly give them the benefit of the doubt. But they’re not, and science knows it. Ryan can drag out mental illness, germs or a host of minor scientific discoveries (in comparison) that are naturalistic, but they’re not really comparable to the big ones under discussion. The analogy is unconvincing.

But then when you throw in the evidence in favour of religious belief, the scales start to tip in my view. Ockham’s Razor suggests the God Hypothesis is a more logical explanation than the twisting contortions we are currently being offered as scientific alternatives.

I may be wrong, but I don’t think even Hume was suggesting that his argument re miracles negated the need for a first cause creator.

I explained why Science of the Gaps rather than God of the Gaps. (I’m assuming you read today’s response to your reply.) God has lost every contest in which winning is possible. You’ve written a book about an unwinnable contest that can never be conclusively decided and declared the gap must be filled by God. You are asking us to believe that despite scientific explanations trumping supernatural explanations at every trumpable turn, on this issue, we have to give supernatural explanations the benefit of the doubt.

I ask again: what are the odds of that? I know, they’re not precisely calculable, but you’re usually such a big fan of betting with the odds, and history does have a pretty strong bias in favour of chemistry over alchemy, psychiatry over demon possession, neurology over faerie lore, etc.

Given the physics required for interstellar spaceflight (and I cover this in The Divinity Code too), it may actually be impossible for us to reach another star system, let alone send back intelligible data within a useful timeframe.

Given the physics required for interstellar spaceflight, the universe could give rise to many different instances of life at various times and places, and none of them would ever have the chance to meet. There is some middle ground between “life on earth is unique!” and “you shouldn’t be able to crack a telecope out without seeing life in the skies!”

And finally…

I would have thought that, objectively, if you were created by a divine being, it automatically gave your life purpose regardless of whether the created thing thinks so or not.

There’s no such thing as “objectively… purpose”. You can’t derive an ought from an is. If you think being created by a big divine being means you should act some particular way, you must have started off with the position that you should do what divine beings want you to do if they happen to create you.

Consider your example:

A dumb machine made by a human still has a purpose for its existence, regardless of whether it recognises it.

Look at what “purpose for its existence” means. It means something the human wants to use it for – a means to fulfilling some desire of the human. That’s not a purpose in any existential sense – it’s simply being the object of another being’s desire.

Is that really what you mean by purpose when you speak of the purpose of your own life? A means to someone else’s end?

Firstly the “purpose” issue. If God created humans for his purposes, then yes, your life has a purpose independent of what you might percieve that to be.

Divine plaything, a means “to someone else’s end”? I guess that’s in the eye of the beholder, and that’s the whole reason Christianity hangs on a choice for faith, rather than a decree.

God doesn’t force you to accept him.

God’s purpose for your life might be the best purpose possible for you. You may choose not to embrace it, as is your right under free will.

Yes I did read your post, but it got caught up in the wider issue here.

I wouldn’t be too swift to authoritatively declare that science has disproven demonic possession or influence on mental health. I’ve seen some of these things first hand…and I’ve seen reports that a growing number of psychologists/psychiatrists are taking seriously the importance of religious faith in curing some of these issues where drugs have failed.

Even so, we agree that God is not causing lightning, (although this doesn’t rule out his capacity to cause a lightning strike in a particular circumstance by divine fiat), or other natural phenomena.

However, as I said earlier and you are evading it, the comparisons you draw are several orders of magnitude away from the creation of the universe and the creation of life. Those events are singularities of huge significance. The fact that we haven’t seen another universe spring up in 15 billion years lends weight to it not being part of natural ongoing processes..

Regardless, you actually missed my main point. Yes, I argue that the probability of all this points to God, but I acknowledge in the book that this is my interpretation of the hard data. Equally I point out that naturalists argue for a natural origin based on their reading. WHAT I AM GETTING AT HOWEVER, is that naturalists are in the end using a faith-based argument, just as you are, to defend their end-case scenario.

Nothing wrong with that per se, as long as we all recognise THAT IT IS NOT A “SCIENTIFIC” ARGUMENT. It is an appeal to Science of the Gaps in exactly the same way I might appeal to God of the Gaps (you claim).

To be fair, you recognise this in the bigger sense, that the argument cannot be proven one way or the other. Good, we agree on that. But suggesting that simply because science can explain the routine, that therefore it is likely to be able to explain singularities (when the arguments are getting more ridiculous and desperate by the year) – frankly I don’t think you’re in a strong position to confidently make that analogy.

All you are doing is masking your appeal to Science of the Gaps in the grounds of probability…which is exactly what I’m doing. Both of us still have to believe our respective conclusions on faith, however, regardless of how much evidence we mount.

All you are saying is that you admit that while science trumps supernatural explanations at every testable issue, you fall back on untestable issues and claim their very untestability (unique, unreproducable) makes them “hugely significant” and thus somehow outweigh the overwhelming tendency for scientific explanations to trump supernatural explanations practically every single time.

In the analogy of the thousand men and the lie detector, what you’re saying is that after 999 men were found to have lied in their lives, it’s reasonable to believe that the now dead and untestable 1000th man had never told a lie. Why? Precisely because he’s dead and untestable – making him unique and a million times more significant than the others, and thus unlikely to follow the established pattern.

And come on. You don’t seriously think “the fact that we haven’t seen another universe spring up in 15 billion years lends weight to it not being part of natural ongoing processes.” You know perfectly well that if universes were springing up, we by definition would not be seeing them.

It is possible that the most accurate explanation for the existence of the universe (if such a notion is intelligible) or abiogenesis is a supernatural one. And it is possible that the most accurage explanations are scientific ones. But you seem to think that the fact that they’re both possible puts them on an even footing, and the choice is a matter of taste/bias.

It’s not. It’s not an even footing. Naturalistic explanations have repeatedly, repeatedly, repeatedly trumped supernatural ones. It has never been the case in the experience of the human race that if one assumes there is a naturalistic explanation for some physical phenomenon, you will be proven wrong. It has never been the case in any testable situation in the history of the human race that if one assumes there is a supernatural explanation for some physical phenomenon, you will be proven correct.

Supernatural explanations are on the back foot. All you have done is retreated to untestable phenomena, declared them “significant” and so worth more points than the whole history of science’s triumphs, and claimed that it’s petty bias not to believe a big invisible being is the correct explanation this time.

It’s not faith to believe that if something has happened a million times before, it’ll happen again this time. It’s the only reasonable attitude. It could be wrong. This could be the one time. But it is unreasonable to believe that. If you apply the term “faith” equally to expecting unprecedented exceptions to rules and expecting things to conform to rules, I really don’t know what you mean by the word at all.

On page 180 of The Divinity Code you’ll see a story recounted involving a US sociologist and theologian. Perhaps you can tell me a credible “natural” explanation for the story. You don’t need to do it yet, but you can keep this in mind for when you get to that part of the book.